8 & -7 (see below)
1. x * y = -56
2. x + y = 1
We can rewrite 2. as y = -x + 1
We can then substitute this into 1. to give:
x (-x + 1) = -56
-x2 + x = -56
-x2 + x + 56 = 0
This factors to:
(-x + 8) (x + 7) = 0
Therefore:
-x + 8 = 0
x = 8
and
x + 7 = 0
x = -7
Therefore the two numbers are 8 & -7.